1. Field of Invention
The invention generally relates to testing and calibration of optical and electro-optical modules, generically referred to herein as xe2x80x9cmodulesxe2x80x9d or xe2x80x9coptical modules.xe2x80x9d More specifically, the invention relates to systems, apparatuses and methods for performing parallel, asynchronous testing and calibration of optical and/or electro-optical modules.
2. Description of Related Art
Electronic manufacturers that produce large volumes of identical components have sought to improve widely-used serial testing techniques by employing parallel testing schemes. Such parallel test schemes subject a large number of identical electronic devices to the same test. The test cycle for such electronic components is relatively short and the testing of a plurality of such components is initiated simultaneously. In other words, there is known a synchronous, parallel testing scheme for testing electronic components.
Optical networking equipment manufacturing presents difficult challenges not faced by electronic equipment manufacturers. It is quite common for optical networking equipment manufacturers to specially build a set of optical networking equipment to order. Furthermore, the orders are often unpredictable and sporadic which means that the manufacturing must be highly adaptable and dynamic.
In other words, optical networking equipment manufacturing is a high mix environment in which a variety of different modules are made. The mix of equipment may change on a daily or even hourly basis. This is particularly true for WDM (wave division multiplexed) or DWDM (dense wave division multiplexing) equipment in which a large number of, for example, transmitters, receivers, and transceivers are built each of which may have a different construction and may be designed for a different channel wavelength. Thus, it is inefficient to dedicate a production line or testing station to a particular module or component.
The conventional method of manufacturing optical and electro-optical components and modules is essentially a serial process. For example, a component or module is partially assembled, then tested, then more fully assembled, then tested again, and so on in a sequential fashion. Such serial assembly and testing is inefficient and labor intensive.
Typically, test stations are used to test a component or module in the assembly line. Such test stations are designed to perform a specific test or set of tests in sequence. The test station and the test sequence is specific to the product or assembly line. As such, the typical test station is not flexible and leads to inefficient utilization of test equipment and labor resources. Furthermore, the high mix environment faced by optical networking equipment manufacturers makes using a parallel testing architecture inadequate since different tests needs to be performed on the high mix of components.
The invention may be characterized as an optical module testing system for testing a plurality of optical modules, including a plurality of optical test signal generators each capable of outputting an optical test signal; a plurality of input switches each optically communicating with the optical test signal generators and a corresponding one of the optical modules to be tested; a plurality of optical test equipment; a plurality of output switches each optically communicating with the optical test equipment and a corresponding one of the optical modules to be tested; and a controller operatively connected to the optical test signal generators, the input switches, the output switches, and the optical test equipment, the controller controlling the optical test signal generators, the input switches, the output switches, and the optical test equipment to perform testing of the plurality of the optical modules.
Furthermore, the system may use a database of testing information operatively connected to the controller; the controller configuring at least one the optical test signal generators, the input switches, the output switches, and the optical test equipment according the database of testing information.
To permit an operator to select a test procedure an input device may be operatively connected to the controller, the input device permitting an operator to select a test procedure for each of the optical modules to be tested; the controller utilizing the selected testing procedure for each optical module to control at least one the optical test signal generators, the input switches, the output switches, and the optical test equipment and perform testing of each of the optical modules.
In addition, a database of testing information may be operatively connected to the controller; the controller downloading testing information from the database according to the selected testing procedure and controlling at least one the optical test signal generators, the input switches, the output switches, and the optical test equipment according the database of testing information.
To simulate real-world optical signals, the invention may further include an optical signal degrader optically communicating with one of the optical test signal generators; one of the input switches optically communicating with the optical signal degrader and one of the optical modules; the controller also operatively connected to the optical signal degrader; the controller controlling the optical signal degrader to degrade the corresponding optical test signal to a desired signal-to-noise ratio.
Moreover, the controller may control the optical test signal generators, the input switches, the output switches, and the optical test equipment to perform parallel asynchronous testing of the optical modules.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.